tea-strainer vs strainer

tea-strainer and strainer both are nouns.

Word	Noun	Adjective	Verb	Adverb
tea-strainer	Yes	No	No	No
strainer	Yes	No	No	No

As nouns, strainer is a hypernym of tea-strainer; that is, strainer is a word with a broader meaning than tea-strainer:

tea-strainer: a device to keep back tea leaves when pouring a cup of tea
strainer: a filter to retain larger pieces while smaller pieces and liquids pass through

tea-strainer (noun)	strainer (noun)
a device to keep back tea leaves when pouring a cup of tea	a filter to retain larger pieces while smaller pieces and liquids pass through